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Show HN: A virtual whiteboard for working or teaching remotely

whiteboardfox.com

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Re: Show HN: A virtual whiteboard for working or teaching remotely

#23
post #13
post #12

I tried opening "my" whiteboard in a second tab in Firefox (on Windows). The second tab's view is distorted, it reminds me of having a badly programmed modulo register on the Amiga. Which doesn't say much to most, I guess... It looks as if the scan lines are mis-aligned, i.e. as if some pixels in each line is missing from each, causing the resulting image to be slanted and distorted.

Hmmm - send me a screenshot. I'll take a look.

"You have mail". Good luck. :)

Re: Show HN: A virtual whiteboard for working or teaching remotely

#24
post #10

Earlier quoted context omitted.

Nicely done, website is nice and it's great that you can just click and get started straight away. In your comment you said you moved away from mySQL, what exactly do you store in the DB? Which leads to the question: how do you transfer the drawing data between clients? I guess it's not a case of uploading a Canvas as an image?

The drawing is basically a list of strokes, and a stroke is a list of points - that is, (x, y) coordinates. So the database is mostly a huge table of (x,y) coordinates. Uploading the entire canvas would far too inefficient - I simply upload the points. The transfer between two clients uses a technique called 'long polling'. That is, the client sends an HTTP request to the server, and the server doesn't respond until…

Did you end up using any libraries for the communication, such as socket.io? (http://socket.io/)

Re: Show HN: A virtual whiteboard for working or teaching remotely

#27
Oh my god. I love this! I've been waiting for a simple polished solution for this for years and years. When skype came along and then we got skype extensions, I thought they'd solve this, but oh no. Every solution that has come out so far has been mediocre at best. I'm glad someone decided to tackle this properly. I haven't had chance to try on iPad, but from the homepage it seems it'll work fine there as well?
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